Method of making cylinders



July 16, 1929. J. o. ALMEN 1.7219

I METHOD OF MAKING CYLINDERS Filed Feb. 24, 1925 INVENTOR 70 7 a .Tamv 0I LMEIY Patented July 16, 1929.

UNITED STATES JOHN O. ALMEN, OF SEATTLE, WASHINGTON.

METHOD OF MAKING CYLINDERS.

Application filed February 24, 1925. Serial No. 11,123.

My invention relates to improvements in internal combustion engines andparticularly to the construction and mode of assembly of cylinders andcylinder heads for use in internal combustion engines.

In the construction of engines of the internal combustion type it isgenerally desirable that they be made as light in weight as is possiblewithout impairing the durability and efficiency. Furthermore it has beenfound practical to construct the body of the engines and the cylinderheads of aluminum, since this metal meets the above requirements and atthe same time is all the more desirable on account of the property ofaluminum to quickly absorb and to radiate the heat incidental toexplosions of fuel charges within the cylinder. It is not desirable,however, that the cylinder walls be made of this particular metal since,for one reason, it is not as capable as steel in resisting wear causedby the operation of pistons therein.

In view of the above, it has been the object of the present invention toprovide a method of assembling and securing together certain engineparts, particularly the cylinders and cylinder heads of internalcombustion engines wherein the former are constructed of a relativelyhard and durable metal such as steel and the latter are of a lightermetal with a greater co-eflicient of expansion and of radiation, such asaluminum.

Specifically stated, the invention resides in the details ofconstruction of the parts and in the means for and method of connectingthe steel cylinder sleeves to the aluminum heads.

Another object resides in the details of construction which provides foran easy replacement of parts.

In accomplishing these and other objects of the invention, I haveprovided the improved details of construction, the preferred forms ofwhich are illustrated in the accompanying drawings, wherein Figure 1 isa central, longitudinal section of an internal combustion engine whereinthe cylinder walls and cylinder heads are constructed and joinedtogether in accordance with the present invention.

Figure 2 is an enlarged sectional view of Figure 3 1s an enlarged viewshowing in cross section an end portion of the cylinder sleeve and thejoint between it and the aluminum head. particularly illustrating thelocking lands on the cylinder sleeve.

Figure 4 is a sectional detail view illustrating the same method anddetails of construction as applied in the mounting or assembly of valveseats.

Referring more in detail to the drawings 1 designates, in its entirety,an engine wherein the cylinder sleeves and heads are constructed andjoined together in accordance with the present invention. In thisparticular type of engine the drive shaft 2 is rotatably mounted inparallel relation to the axial line of the cylinders which are arrangedcircularly about it, and the pistons 3 are connected to the shaftthrough the intermediacy of a swash plate, or the like, as designated at4, and which is revolubly mounted on a journal 5 formed on the shaft atan angle that is oblique with respect to its axial line.

In this construction the body portion of the engine and the cylinderheads 6 are cast from aluminum and the cylinder sleeves 7 are of steel.In preparing these parts for assembly the aluminum heads 6 are boredsmooth about their interior surface, and the end of the steel sleeve 7that is to be applied therein, is turned down smooth, except for aplurality of encircling, spaced apart lands 8 that are left sharp ontheir outer or peripheral edges and which have perpendicular surfaces 9faced away from the head andinclined surfaces 10 directed toward thehead. The inside diameter of the head is lesser than the diameter of theend of the sleeve that is to be applied there to when these parts are atthe same degree of temperature and before assembling.

In assembling these parts, the portion of the sleeve provided with thelands 8 is first painted with castor oil which serves to better seal thejoint to be made. The aluminum head is then heated to about 700 to 750degrees Fahrenheit, so that it is sufliciently expanded thereby to allowthe sleeve at normal temperature to be dropped into the bore provided. IThe inner end of the sleeve the sleeve that the lands 8 are completelyembedded and the joint made perfectly tight. During operation of theengine the head does not heat to a degree much above 212 degreesFahrenheit for the reason that it is jacketed and water cooled andatthis degree it does not expand sufficiently 'to loosen the joint.

This method of assembling provides an absolutely tight and non-leakingjoint which is superior to a threaded connection for .the reason thatthe latter can not be made gas tight. The parts are easily assembled andmay be disassembled if such should be desired to become necessary byapplying heat to the head sufiici'cnt to expand it to the diameterthatWill permit the sleeve to be withdrawn.. This provides for quick andeasy replacement of worn or damaged sleeves. v I

In Figure 4, I have illustrated the same methods of construction andapplication as alpplied to the assembly of valve parts. In t is figure,20 designates a valve head on a stem 21, and 22 a steel ring that is setinto a manifold or housing 23 and provided with a seat 24 against whichthe valve operates. The ring 22 may be of steel and is provided withencircling lands 25 Y and the housing may be of aluminum. In theassembly of these parts,- the housing is'heated as was previouslydescribed in connection with the cylinder assembly and then the ring isdropped in place and the housing allowed to cool and to shrink onto thering.

While I have illustrated the cylinder assembly in a certain type ofengine, it is to be understood that it is not to be confined only tothis type, but also is practical and.

can be satisfactorily used in various types of gas engines such as areused 1n automobiles, airplanes or for stationary work.

. cient to receive the turned ends of the sleeve,

inserting the turn-down ends of the sleeves in said bores and againstthe shoulders therein, and then allowing the heads to cool and tightenby contraction about the sleeve ends so that the lands are imbedded inthe metal of the head.

Signed at Seattle, King County, Washington, this 16th day of May, 1924:.

JOHN O. ALMEN.

